Alkylation with separate butene streams including isobutylene

Abstract

A process for producing an alkylation reaction product from an isoparaffin and an olefinic reactant containing 1-butene, 2-butene and isobutylene by fractionating the olefinic reactant into a 2-butene fraction and a separate 1-butene and isobutylene fraction. The 2-butene is charged to an HF alkylation reaction zone with isobutane. The mixture is heated by the endothermic reaction, and the fraction comprising 1-butene and isobutylene is then added to the unitary reaction zone. It is possible to alkylate these olefins at conditions which are close to the optimum conditions, using a single reactor vessel, which operates at different temperatures without the necessity for heat exchange means.

I claim as my invention: 
     
       1. A process for alkylating an isoparaffin with a stream comprising 2-butene and a separate stream comprising 1-butene and isobutylene which comprises a. passing at least a portion of the isoparaffin in admixture with the 2-butene stream and HF acid catalyst to an upstream portion of a reactor wherein the 2-butene reacts with the isoparaffin in an exothermic reaction which increases the temperature of the reactants, acid, and alkylate,   b. charging to a downstream portion of the reactor a stream comprising 7-butene and isobutylene,   c. separating a hydrocarbon phase comprising alkylate products and unreacted isoparaffins; from HF catalyst phase, and   d. separating said alkylate products from said hydrocarbon phase of step (c).   
     
     
       2. Process of claim 1 wherein the reactor is a single, elongated vessel. 
     
     
       3. Process of claim 1 wherein the reactor operates adiabatically. 
     
     
       4. Process of claim 1 wherein the isoparaffin reactant is isobutane, and the isobutane is supplied in a molar ratio equivalent to 2:1 to 24:1, based upon the total amount of olefin charged to the reactor. 
     
     
       5. Process of claim 1 wherein the acid to hydrocarbon ratio in the reactor is 1:1 to 2:1. 
     
     
       6. Process of claim 1 wherein the temperature difference between said upstream portion and said downstream portion of the reactor is 1° to 10° C. 
     
     
       7. Process of claim 1 wherein additional isoparaffin is charged to said downstream portion of the reactor.